Electric motor with power supply circuit supplying isolated electric power

ABSTRACT

Circuitry for controlling motors, such as a brushless motor (BLM), is disclosed. The circuitry may comprise one or more inputs for receiving rotor position signals from one or more Hall effect sensors that detect the position of, for example, a BLM rotor. The circuitry may also comprise an input for receiving a pulse width modulated speed control signal. The circuitry generates one or more drive signals, each of which may comprise a logical combination (e.g., a logical AND combination) of the speed control signal and a rotor position signal, for controlling power switches that are coupled to electromagnets of the BLM.

RELATED APPLICATIONS

This application is a continuation application of U.S. patentapplication Ser. No. 12/397,227, filed Mar. 3, 2009, which is acontinuation-in-part of U.S. patent application Ser. No. 12/041,580,filed Mar. 3, 2008, now U.S. Pat. No. 7,795,827 and also is anon-provisional application of U.S. Provisional Patent Application61/059,596, filed Jun. 6, 2008. Each of the foregoing applications ishereby incorporated herein by reference in its entirety and is to beconsidered part of this specification.

BACKGROUND

1. Technical Field

The disclosure relates to circuitry for controlling a brushless motor(hereinafter referred to as a “BLM”).

2. Description of the Related Art

Recently, a BLM for driving a blower or a fan for an HVAC, or a pump hasbeen widely used. The use of a BLM is closely related to home and workenvironments in daily life, including apartments, offices, or factories,etc. A motor for a blower or a fan for an HVAC, or a pump has asignificant amount of electric power consumption, which may range fromseveral times to several ten times the amount used in different fieldssuch as, e.g., the field of industrial mechanical devices or machinetools, etc., due in part because such a motor is required to be operatedcontinuously for typically at least several hours or more per day.Therefore, a motor for a blower or a fan for an HVAC, or a pump, whichrequires a long time or a continuous operation, has a very large amountof energy consumption. Particularly, the electric power consumptionrequired for driving a blower or a fan for an HVAC, or a pump takes avery large portion in a BLM. Further, the use of a BLM affects directlythe efficiency and performance of a driving system for an HVAC or apump.

Accordingly, a motor having high-efficiency for saving energy has beenrequired, and a development of an intelligent control system capable ofcontrolling a motor having high-efficiency conveniently and stably hasbeen required.

In the past, an AC induction motor with an inexpensive and simplestructure has been mainly used as a motor having high-efficiency.However, there is a problem that causes an unnecessary over-speedoperation and hence a significant loss of electric power because this ACinduction motor is difficult to control. For example, it is difficult tocontrol a speed necessarily required for providing an energy saving andconvenient operation conditions. Meanwhile, the AC induction motor hasused a separate inverter in order to solve this kind of problem.However, the use of a separate inverter causes a noise problem, and hasa certain limit in providing a program suitable for various requiredoperation conditions, in addition to a speed controlling, due to a lowoperation efficiency in terms of economic efficiency (an energyconsumption amount compared to costs).

Further, motors for driving a fan using a BLM or an electricallycommuted motor (hereinafter referred to “ECM”) have recently beenpracticed. However, the motors for driving a fan using an ECM aredesigned to be used mainly as motors for driving simply a compact orlow-capacity fan with 100 Watts or less, and thus have a limit in thatthey are not suitable for an HVAC designed for the use of ahigh-capacity housing or industrial purpose.

In the meanwhile, technologies relating to an apparatus and a method forcontrolling an ECM used for an HVAC with a housing and industrialpurpose are disclosed in U.S. Pat. No. 5,592,058 (hereinafter referredto “'058 patent”) allowed to William R. Archer, et al. and entitled“Control System and Methods for a Multi-parameter ElectronicallyCommutated Motor.” However, because the control system and methods for amulti-parameter electronically commutated motor disclosed in '058 patentuse AC half waves as input signals for various system parameters, use aseparate programmable memory for storing the various system parameters,and use separately a complicated circuit such as ASIC, which is usedwith being connected to a means for sensing a position of a rotor and acurrent control circuit, the '058 patent has a problem in that anoverall system and controlling processes are complicated.

Further, in the control system and methods for the multi-parameterelectronically commutated motor disclosed in the '058 patent, since amicroprocessor controls an ECM depending on parameter signals pre-storedin the programmable memory, it is impossible to respond properly in realtime when, for example, an abnormal operation condition may occur.

Still further, in the control system and methods for the multi-parameterelectronically commutated motor disclosed in the '058 patent, the meansfor sensing the position of a rotor may be made in a sensor-less manner.However, in case of sensing a position of a rotor using this sensor-lessmanner, there are problems that an unstable transient phenomenon mayoccur at a startup of the ECM and a high possibility of a mal-operationmay occur due to a vulnerability to an electromagnetic noise.

In the meanwhile, conventional control systems of a motor do not havemeans capable of controlling efficiently a system for driving variouskinds of blowers or fans for an HVAC, or a pump, such as means orfunctions including a non-regulated speed control (NRS) operationfunction, a regulated speed control (RS) operation function, a constanttorque control function, a constant air flow/constant liquid flowcontrol function, a remote communication and monitoring function, anetwork control means or function capable of controlling a drive ofmultiple fans or pumps using a mod bus, and a data logging means orfunction capable of checking operation states or records of a controlsystem for an HVAC or a pump.

Moreover, conventional control systems of a motor have a problem in thatthey cannot provide the functions described by a single integratedcontrol circuit and program.

The foregoing discussion is to provide background information and doesnot constitute an admission of prior art.

SUMMARY

An electronic circuit for controlling a brushless motor (BLM) isdisclosed. In some embodiments, the electronic circuit comprises: firstand second inputs for respectively receiving first and second digitalposition signals from first and second Hall effect sensors, the firstand second Hall effect sensors for detecting the angular position of aBLM rotor; a third input for receiving a digital pulse width modulatedspeed control signal; a first logic gate for generating a first drivesignal that comprises a logical combination of the first digitalposition signal and the speed control signal; and a second logic gatefor generating a second drive signal that comprises a logicalcombination of the second digital position signal and the speed controlsignal.

In some embodiments, an electronic circuit for controlling a brushlessmotor (BLM) comprises: a first input to receive a first position signalfrom a first sensor that detects the angular position of magnetic poleson a BLM rotor, the first position signal having active periods andinactive periods; a second input to receive a second position signalfrom a second sensor that detects the angular position of magnetic poleson the BLM rotor, the second position signal having active periods andinactive periods; control circuitry to receive the first positionsignal, the second position signal, and a speed control signal, and togenerate first and second drive signals based on the position and speedcontrol signals, wherein the first and second drive signals eachcomprise a plurality of inactive periods that correspond to therespective inactive periods of the first and second position signals,and wherein the first and second drive signals each further comprise aplurality of pulses that correspond to each of the respective activeperiods of the first and second position signals, a first bridgeconfiguration of switches for receiving the first drive signal, and forcoupling a power source to a first drive output during each of theplurality of pulses of the first drive signal; and a second bridgeconfiguration of switches for receiving the second drive signal, and forcoupling the power source to a second drive output during each of theplurality of pulses of the second drive signal.

An electronic method for controlling a brushless motor (BLM) isdisclosed. In some embodiments, the electronic method comprises:receiving first and second digital position signals from respectivefirst and second Hall effect sensors, the first and second Hall effectsensors for detecting the angular position of magnetic north poles on aBLM rotor; receiving a digital pulse width modulated speed controlsignal; generating a first drive signal that comprises a logicalcombination of the first digital position signal and the speed controlsignal, the first drive signal for controlling a first set of one ormore power switches communicatively coupled to a first set of one ormore BLM electromagnets; and generating a second drive signal thatcomprises a logical combination of the second digital position signaland the speed control signal, the second drive signal for controlling asecond set of one or more power switches communicatively coupled to asecond set of one or more BLM electromagnets.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of a control system for controlling abrushless motor according to one embodiment.

FIG. 2 a is a cross-section view of a 2 phase and 3 phase combined typebrushless motor being used in one embodiment illustrated in FIG. 1.

FIG. 2 b is a cross-section view of a conventional 2 phase brushlessmotor being used in one embodiment illustrated in FIG. 1.

FIG. 3A illustrates a first set of example signal waveforms in the phaselogic control circuit during various phases of rotation of the BLM rotoraccording to some embodiments.

FIG. 3B illustrates a second set of example signal waveforms in thephase logic control circuit during various phases of rotation of the BLMrotor according to some embodiments.

FIG. 4A is a view of a first 2 phase logic control circuit being used insome embodiments.

FIG. 4B illustrates two states of a logic switch used to control thedirection of rotation of a BLM.

FIG. 4C is a view of a second 2 phase logic control circuit being usedin some embodiments.

FIG. 5A is a detailed view of a first power switch circuit being used insome embodiments.

FIG. 5B illustrates two states of a full bridge circuit used to supplypower to the armature windings of a BLM.

FIG. 5C is a detailed view of a second power switch circuit being usedin some embodiments.

FIG. 6 is a detailed circuit view of a control system being used in oneembodiment.

DETAILED DESCRIPTION OF EMBODIMENTS

In some embodiments there is a control system for controlling a motorfor an HVAC or a pump, where a microprocessor receives multiple controlsignals for controlling a motor for an HVAC or a pump and controls themin real time.

In some embodiments there is a control system for controlling a motorfor an HVAC or a pump, which is capable of sensing abrupt load variationof a motor and thus procuring stability and capable of protecting themotor and the control system from a change of an environmentaltemperature or an abnormal temperature change of the motor itself.

Further, there is a control system for controlling a motor for an HVACor a pump, which has a built-in isolated power supply to be used for acontrol system for controlling external inputs and thus is capable ofaccessing easily various control command signals relating to a mastercontrol system of the motor for an HVAC or a pump, even without aseparate external power supply source.

Further, in some embodiments there is a control system for controlling amotor for an HVAC or a pump having an opto-isolated communication meanscapable of transmitting and receiving various control program data and ameans where a DC voltage signal (Vdc) or a pulse modulation signal to beused as a control signal for controlling a speed of the motor can beinputted therein through one input port and processed accordingly.

According to some embodiments, there is a control system for controllinga motor for a heating, ventilation and air conditioning unit (HVAC) or apump comprising: an opto-isolated speed command signal processinginterface into which a signal for controlling a speed of the motor isinputted and which outputs an output signal for controlling the speed ofthe motor being transformed as having a specific single frequency; acommunication device into which a plurality of operation controlcommands of the motor; an opto-isolated interface for isolating theplurality of operation control commands inputted through thecommunication device and the transformed output signal for controllingthe speed of the motor, respectively; a microprocessor, being connectedto the opto-isolated interface, for outputting an output signal forcontrolling an operation of the motor depending on the plurality ofoperation control commands and the transformed output signal forcontrolling the speed of the motor; a sensor, being connected to themotor, for outputting a rotor position sensing signal of the motor; alogic control circuit, being connected to the opto-isolated interface,the microprocessor, and the sensor, respectively, for adding the rotorposition sensing signal and the output signal for controlling theoperation of the motor; a power switch circuit being connected to feedelectric power to the motor; a gate drive circuit, being connected tothe logic control circuit and the power switch circuit, respectively,for driving the power switch circuit; and a power supply device beingconnected to the logic control circuit, the power switch circuit, andthe gate drive circuit, respectively, for feeding electric powerthereto.

Various features of embodiments provide many advantages, including:

1. Various operation controls required in a motor for an HVAC or a pumpmay be made in real time.

2. Operation efficiency of a motor for an HVAC or a pump issignificantly enhanced so that it is possible to operate a motor at lowconsumption of electric power and in a various and intelligent manner.

3. A control system of a motor for an HVAC or a pump may be embodiedwith a simple configuration.

4. It is convenient to use a control system of a motor for an HVAC or apump because a separate built-in power supply device for feeding anexternal power supply is included therein.

5. It is possible to monitor any troubles, operation efficiency, and acondition on a stable operation of an HVAC or a pump in real time sincevarious operation data information (e.g., operation current, voltage,speed, and temperature, etc. which are processed by a control system ofa motor for an HVAC or a pump in some embodiments) is possible to betransmitted to an external system.

Further features and advantages can be obviously understood withreference to the accompanying drawings where same or similar referencenumerals indicate same components.

Hereinafter, embodiments are described in more detail with reference tothe preferred embodiments and appended drawings.

FIG. 1 is a block diagram of a control system for controlling abrushless motor according to one embodiment, FIG. 2 a is a cross-sectionview of a 2 phase and 3 phase combined type brushless motor being usedin one embodiment illustrated in FIG. 1, and FIG. 2 b is a cross-sectionview of a conventional 2 phase brushless motor being used in oneembodiment illustrated in FIG. 1.

Referring to FIG. 1, a 2 phase and 3 phase combined type brushless ECMillustrated in FIG. 2 a or a conventional 2 phase brushless ECMillustrated in FIG. 2 b may be used as a motor 2 to be controlled by acontrol system for an HVAC or a pump. The 2 phase and 3 phase combinedtype brushless ECM illustrated in FIG. 2 a is a motor where a 2 phasearmature and a 3 phase rotor are combined. More specifically, a specificstructure and operations of the 2 phase and 3 phase combined typebrushless ECM illustrated in FIG. 2 a is disclosed in more detail inKorean Patent No. 653434 (hereinafter referred to “434 patent”)registered on Jan. 27, 2006, entitled “Brushless DC motor,” which wasfiled on Apr. 29, 2005 as Korean Patent Application No. 10-2005-0035861by the present inventor and applicant. The disclosure of '434 patent isincorporated herein by reference. Because one purpose of someembodiments is to provide a control system for controlling the 2 phaseand 3 phase combined type brushless ECM illustrated in FIG. 2 a or theconventional 2 phase brushless ECM illustrated in FIG. 2 b and themotors illustrated in FIGS. 2 a and 2 b are all known, the specificstructures and operations of the 2 phase and 3 phase combined typebrushless ECM illustrated in FIG. 2 a and the conventional 2 phasebrushless ECM illustrated in FIG. 2 b will not be described in detail inthe present specification. Moreover, although a control system accordingto some embodiments is described to be applied to the conventional 2phase and 3 phase combined type brushless ECM and 2 phase brushless ECMin an exemplary manner, a skilled person in the art may fully understandthat a control system according to some embodiments shall be used tocontrol a single phase ECM or a typical ECM.

Referring back to FIG. 1, a motor 2 may be used for driving a blower ora fan used for an HVAC, or driving a pump (hereinafter “a blower or afan” and “a pump” may be refereed to commonly as “a pump”). A controlsystem for controlling a motor 2 for a pump 1 according to someembodiments comprises an opto-isolated speed command signal processinginterface 14 into which a signal for controlling a speed of the motor 2is inputted and which outputs an output signal for controlling the speedof the motor 2 being transformed as having a specific single frequency;a communication device 13 into which a plurality of operation controlcommands of the motor 2; an opto-isolated interface 11 for isolating theplurality of operation control commands inputted through thecommunication device 13 and the transformed output signal forcontrolling the speed of the motor 2, respectively; a microprocessor 10,being connected to the optoisolated interface 11, for outputting anoutput signal for controlling an operation of the motor 2 depending onthe plurality of operation control commands and the transformed outputsignal for controlling the speed of the motor 2; a sensor 3, beingconnected to the motor 2, for outputting a rotor position sensing signalof the motor 2; a logic control circuit 9, being connected to theopto-isolated interface 11, the microprocessor 10, and the sensor 3,respectively, for adding the rotor position sensing signal and theoutput signal for controlling the operation of the motor 2; a powerswitch circuit 4 being connected to feed electric power to the motor 2;a gate drive circuit 7, being connected to the logic control circuit 9and the power switch circuit 4, respectively, for driving the powerswitch circuit 4; and a power supply device 5 being connected to thelogic control circuit 9, the power switch circuit 4, and the gate drivecircuit 7, respectively, for feeding electric power thereto. Hereinbelow, all elements and their cooperative relationships of a controlsystem for controlling a motor 2 for a pump 1 according to someembodiments will be described in more detail between the

First, a control system for a pump 1 according to some embodimentsincludes an opto-isolated speed command signal processing interface 14.The opto-isolated speed command signal processing interface 14 isconnected to a central control system 15. Further, the an opto-isolatedspeed command signal processing interface 14 may have a separatebuilt-in microprocessor (see reference numeral 146 illustrated in FIG.6) which outputs a pulse width modulation (PWM) signal for controlling aspeed being transformed to a specific single frequency (e.g., 80 Hzfrequency according to some embodiments) and maintained the transformedspecific frequency. Therefore, the opto-isolated speed command signalprocessing interface 14 may process a control signal comprised of eithera DC voltage signal (0-10 Vdc) 151 or a PWM signal 151 for controlling aspeed of the motor 2, as well as a start-up signal and a stop signal,all of which are transmitted either from the central control system 15or manually. Especially, even if the PWM signal 151 may have a largefrequency variation width (40 Hz-120 Hz), the PWM signal 151 may feed aPWM output signal having a specific single frequency (e.g., a constantfrequency of 80 Hz), regardless of the large frequency variation width(40 Hz-120 Hz). In this case, the optoisolated speed command signalprocessing interface 14 may transform the PWM signal 151 for controllinga speed having a large frequency variation width (40 Hz-120 Hz) to aspecific single frequency (e.g., 80 Hz according to some embodiments) byusing the separate microprocessor 146 (see FIG. 6). The opto-isolatedspeed command signal processing interface 14 is connected to themicroprocessor 10 through the opto-isolated interface 11. Thus, the DCvoltage signal (0-10 Vdc) 151 or the PWM signal 151 for controlling aspeed of the motor 2 is fed to the microprocessor 10 as a PWM signalwhich is transformed to a specific single frequency (e.g., 80 Hz) by theopto-isolated speed command signal processing interface 14 (hereinafterreferred to “a transformed output signal 151 for controlling a speed ofthe motor”).

Further, a control system for a pump 1 according to some embodimentsincludes a communication device such as RS485 13. RS485 13 is connectedto a factory program device 12 including a pre-determined program whichis programmable by a user. The factory program device 12 may beembodied, for example, by a personal computer (PC). The pre-determinedprogram included in the factory program device 12 may be a programincluding at least one or more operation control commands consisting ofa plurality of operation control commands relating to, for example, NRS,RS, constant torque, constant air flow/constant liquid flow, and aclockwise (CW) rotation/counter-clockwise (CCW) rotation of the motor 2.In an alternative embodiment, an operation control command relating to aCW/CCW rotation of the motor 2 may be inputted through RS485 13, forexample, by a separate toggle switch.

Hereinbelow, specific details of functions and programs necessary foroperating an HVAC and a pump according to some embodiments will bedescribed in more detail.

Referring to FIG. 1 again, an NRS control may be performed in an NRSfirmware program mode which is pre-determined in the microprocessor 10.That is, when an NRS control command is inputted into the microprocessor10 through the RS485 13 and the opto-isolated interface 11, from thefactory program device 12 which is programmable by a user, themicroprocessor 10 is switched to an NRS firmware program mode which ispre-determined in the microprocessor 10. In this NRS firmware programmode, the microprocessor 10 either transforms a PWM output signal to Lowor zero (0), or modulates a pulse width of the PWM output signalincreasingly or decreasingly at a constant rate, and the switched ormodulated PWM output signal is transmitted to the 2 phase logic controlcircuit 9. This may result in that the motor 2 may stop or perform anNRS operation such as a simple speed-variable operation, etc.

A RS control may be performed in a NRS firmware program mode which ispre-determined in the microprocessor 10. That is, when a RS controlcommand is inputted into the microprocessor 10 through the RS485 13 andthe opto-isolated interface 11, from the factory program device 12 whichis programmable by a user, the microprocessor 10 is switched to a RSfirmware program mode which is pre-determined in the microprocessor 10.In this RS firmware program mode, the microprocessor 10 compares andcalculates the transformed output signal 151 for controlling a speed ofthe motor being fed by the opto-isolated speed command signal processinginterface 14 and an input signal 31 a which is sensed by the sensor 3for sensing a rotor position and is outputted through the 2 phase logiccontrol circuit 9. Thereafter, the microprocessor 10 modulates a pulsewidth of the PWM output signal increasingly or decreasinglycorresponding to a comparison and calculation result to maintain aconstant speed which is commanded to the motor 2, and the modulated PWMoutput signal is transmitted to the 2 phase logic control circuit 9.Thus, it is possible that the motor 2 performs an RS operation whichmaintains a constant rotational speed, although a variance in DC voltage54 fed from a power supply device 5 or a load variance of the pump 1 mayoccur.

A constant torque control may be performed in a constant torque firmwareprogram mode which is pre-determined in the microprocessor 10. That is,when a constant torque control command is inputted into themicroprocessor 10 through the RS485 13 and the opto-isolated interface11, from the factory program device 12 which is programmable by a user,the microprocessor 10 is switched to a constant torque firmware programmode which is pre-determined in the microprocessor 10. In this constanttorque firmware program mode, the microprocessor 10 modulates a pulsewidth of the PWM output signal increasingly or decreasingly to vary thespeed of the motor 2 and the modulated PWM output signal is transmittedto the 2 phase logic control circuit 9. More specifically, themicroprocessor 10 compares a pre-determined current value and a loadcurrent value 81 of the motor 2 being fed by a current detection circuit8. Depending on the comparison result, the microprocessor 10 increasesor decreases the pulse width of the PWM output signal for the loadcurrent value 81 of the motor 2 to maintain the predetermined currentvalue constantly. As a result, the speed of the motor increases untilthe motor 2 reaches at a constant torque value when the load currentvalue 81 is decreased, while the speed of the motor decreases until themotor 2 reaches at a constant torque value when the load current value81 is increased. In this manner, it is possible to perform a constanttorque operation maintaining a constant torque.

A constant air flow/constant liquid flow control may be performed in aconstant air flow/constant liquid flow control firmware program modewhich is pre-determined in the microprocessor 10. That is, when aconstant air flow/constant liquid flow control command is inputted intothe microprocessor 10 through the RS485 13 and the opto-isolatedinterface 11, from the factory program device 12 which is programmableby a 16 user, the microprocessor 10 is switched to a constant airflow/constant liquid flow firmware program mode which is pre-determinedin the microprocessor 10. In this constant air flow/constant liquid flowfirmware program mode, the microprocessor 10 modulates the PWM outputsignal calculated as a function value proportional to the speed andcurrent of the motor 2 which is necessary for maintaining a constant airflow/constant liquid flow, depending on a condition determined by aninput of the factory program device 12 regardless of the transformedoutput signal 151 for controlling a speed of the motor. The modulatedPWM output signal is transmitted to the 2 phase logic control circuit 9so that it is possible to perform a constant air flow/constant liquidflow operation. The technologies relating to performing a constant airflow/constant liquid flow operation control is disclosed in more detainin Korean Patent Application No. 10-2007-0122264, entitled “Apparatus tocontrol a multi programmable constant air flow with speed controllablebrushless motor,” which was filed on Nov. 11, 2007 by the presentapplicant. The disclosure of Korean Patent Application No.10-2007-0122264 is incorporated herein by reference.

Meanwhile, a control system for controlling the pump 1 according to someembodiments includes the microprocessor 10. A position signal 31 sensedfrom the sensor 3 for sensing a rotor position is inputted into the 2phase logic control circuit 9, and then the 2 phase logic controlcircuit 9 outputs an input signal 31 a of a rotational speed into themicroprocessor 10. The microprocessor 10 may calculate an RPM of themotor 2 by using the input signal 31 a of a rotational speed. Themicroprocessor 10 also receives a load current signal of the motor 2through the power switching circuit 4 and 17 the current detectioncircuit 8 and calculates a load current value of the motor 2. Further,the microprocessor 10 has a control program which makes the motor 2 tooperate depending on a modulation rate of the transformed output signal151 (typically, 80 Hz) for controlling a speed of the motor fed from thean opto-isolated speed command signal processing interface 14, in amanner that the motor 2 stops at the modulation rate of 0-5% and isoperated with a varying speed at the modulation rate of 5-100%. For thispurpose, the microprocessor 10 also outputs the PWM output signal(frequency: 20 KHz or more), which may vary the speed of the motor 2, tothe phase logic control circuit 9. Further, the microprocessor 10 mayreceive a temperature signal of the motor 2 detected by a temperaturedetection sensor 16, and makes the motor 2 to stop the operation ordecrease the speed thereof when the detected temperature becomes aconstant temperature value or more. Further, the microprocessor 10 mayreceive a DC voltage 54 fed from the power supply device 5 and detectedby a voltage detection circuit 17, and makes the motor 2 to stop theoperation or makes a warning signal when the received DC voltage 54becomes higher or lower than a pre-determined voltage value. Further,the microprocessor 10 may have a firmware program which may output asignal for driving a relay switch 18 to make a notice to an externaluser of an abnormal operation condition, in case that the microprocessor10 decides the abnormal operation condition by determining an operationspeed, current, voltage, and temperature, etc. of the motor 2,separately ort integrally.

Further, a control system for controlling the pump 1 according to someembodiments includes the 2 phase logic control circuit 9. The 2 phaselogic control circuit 9 is connected to the gate drive circuit 7. Thegate 18 drive circuit 7 is connected to the power switch 4 and may drivethe power switch 4. The power switch 4 is connected to the motor 2 andfeeds the DC voltage 54 fed from the power supply device 5 to motorcoils (ØA, ØB) (see FIG. 2) in a switching manner. The 2 phase logiccontrol circuit 9 adds the rotor position sense signal 31 outputted froma Hall sensor 3 for sensing a position of the rotor and the PWM outputsignal having a frequency of 20 KHz or more fed from the microprocessor10. The 2 phase logic control circuit 9 also has a logic switch circuitwhich may switch the motor coils ØA and ØB to maintain or switch therotation direction of the motor 2 depending on a CW command signal or aCCW command signal being inputted through the opto-isolated interface 11so that it is possible to switch the rotation direction of the motor 2.

Still further, a control system for controlling the pump 1 according tosome embodiments includes the power supply device 5 which feeds electricpower. The power supply device 5 rectifies an AC voltage inputted fromoutside and feeds the generated DC voltage 54 to the power switchcircuit 4. The power supply device 5 also feeds a gate drive voltage 53of DC 12-15V, which is dropped by a built-in DC-DC transforming device(not shown) in the power supply device 5, to the gate drive circuit 7.Further, the power supply device 5 feeds a voltage 52 of DC 12-15V tothe 2 phase logic control circuit 9. In the meanwhile, a control systemfor controlling the pump 1 according to some embodiments may include anisolated DC-DC power supply device 6 which is built in separately fromthe input of the AC voltage. A voltage of DC 12V outputted by theisolated DC-DC power supply device 6 is used as a power source for anexternal main system control 14 or a 19 communication device such asRS485 through the opto-isolated interface 11. This built-in typeisolated DC-DC power supply device 6 configures a separate power supplydevice which is electrically isolated from the power supply device 5used for a control system for controlling the pump 1 according to someembodiments. That is, because a built-in power supply device such as theisolated DC-DC power supply device 6 according to some embodiments feedsseparate electric power isolated from the power supply device 5 used fora control system for controlling the pump 1 according to someembodiments, a separate external isolated power supply device to be usedfor accessing an electric signal of a external control device or systemis not required.

Hereinbelow, various advantages will be described in more detail in caseof using a control system for controlling the pump 1 according to someembodiments.

Equipment of the operation of an HVAC or a pump may be used in variousindoor or outdoor environments and is generally required to be operatedstably at a temperature approximately with a wide range of −40° C. to60° C. Further, the motor 2 for an HVAC or a pump reaches at anover-heated condition, a system should not be stopped by switching themotor 2 to be operated a low speed in a safe mode before a break-down ofthe motor 2 occurs. In order to perform functions to satisfy therequirements described above, a control system according to someembodiments includes the microprocessor 10 having a program withspecific algorithms and the temperature detection sensor 16 connected tothe microprocessor 10. The temperature value of the motor 2 detected bythe temperature detection sensor 20 16 becomes a pre-determined stabletemperature value or more, the microprocessor 10 reduces the rotationspeed or the output of the motor 2 up to 40 to 50% at its maximum byusing the program with specific algorithms. Further, when thetemperature value of the motor 2 detected by the temperature detectionsensor 16 returns to a normal temperature, the microprocessor 10increases gradually the rotation speed or the output of the motor 2 toits original pre-determined speed or output by using the program withspecific algorithms.

Further, in case of driving the pump 1, an abnormal condition may occur,including a condition that, for example, a pump circulator is cloggedabruptly or a body part of a human being may be sucked into a pumpinlet, etc., especially in a swimming pool. In such case, a verydangerous abnormal condition may result in such as a break-down of apump, or damages to body or death. When such kind of an abnormalcondition occurs, the speed of the motor 2 is reduced while the loadcurrent of the motor 2 increases abruptly, or the speed of the motor 2is increased while the load current of the motor 2 decreasessignificantly. The microprocessor 10 used for a control system of someembodiments receives a detection signal of the load current 81, therotor position signal 31, the detected temperature signal of the motor 2outputted from the temperature detection sensor 16, and the voltagevariance detection signal of the DC voltage 54 outputted from thevoltage detection circuit 17, and compares and calculates them and theircorresponding predetermined standard values or normal values. Thus, whenthe operation condition of the motor changes abruptly during a normaloperation thereof (i.e., when an abnormal condition occurs), themicroprocessor 10 feeds the 21 variable PWM output signal to the 2 phaselogic control circuit 9 depending on the compared and calculated valuesso that the microprocessor 10 may switch the motor 2 to stop or to beoperated at a minimum operation output condition within a quick periodof time.

Phase Logic Control Circuitry

FIG. 3A illustrates example waveforms of various signals in the phaselogic control circuit 9 during different angular phases of rotation ofthe BLM rotor illustrated in FIG. 2A. Several different segments aredelineated (by dashed vertical lines) for each of the waveforms. Each ofthe segments represents a specified amount of angular rotation of therotor of the BLM illustrated in FIG. 2A. For example, the first segment(from left to right) of each waveform corresponds to the angularrotation from 0°-30° in a clockwise direction (e.g., where the positionof the rotor in FIG. 2A represents the 0° starting point). In likefashion, the second segment of each waveform corresponds to the angularrotation of the rotor from 30°-60° in a clockwise direction, and so onfor each of the subsequent delineated segments in 30° increments.

The signal “φA” is represented by waveform 302. φA is the output of aHall effect sensor positioned on the BLM so as to monitor the rotationalposition of the rotor and to control the excitation of the φA coils inthe armature, as illustrated in FIG. 2A. For example, in someembodiments, this Hall effect sensor is placed in the vicinity of eitherof the φA coils in the armature, though it may also be positionedelsewhere. The signal “φB” is represented by waveform 306. φB is theoutput of a Hall effect sensor positioned on the BLM so as to monitorthe rotational position of the rotor and to control the excitation ofthe φB coils in the armature. For example, in some embodiments, thisHall effect sensor is placed in the vicinity of either of the φB coilsin the armature, though it may also be positioned elsewhere. Asillustrated in FIG. 3A, in some embodiments, the Hall effect sensorsoutput digital signals. For example, the Hall effect sensors may outputa first voltage in the presence of the field from a magnetic north polewhile outputting a second voltage in the presence of the field from amagnetic south pole. In some embodiments, two Hall effect sensors areused to sense the position of the rotor. However, in other embodiments,the position of the rotor can be detected using a different number ofHall effect sensors, or by other means.

In the BLM embodiment illustrated in FIG. 2A, the rotor has six magneticpoles. As such, each magnetic north pole (N) is separated by 120° froman adjacent magnetic north pole, and each magnetic south pole (S) isseparated by 120° from an adjacent magnetic south pole. The north andsouth magnetic poles are arranged in alternating fashion such that eachmagnetic north pole is separated by 60° from an adjacent magnetic southpole. By virtue of this arrangement, in some embodiments, a rotation of120° corresponds to one period of each of the outputs φA and φB from theHall effect sensors. For example, if a magnetic north pole starts offadjacent one of the Hall effect sensors, the output of the sensor may be“low” or “inactive.” However, during 120° of angular rotation, amagnetic south pole will pass adjacent the sensor, during which time itsoutput may transition to “high” or “active,” followed by a magneticnorth pole that causes the output of the sensor to transition back tolow. In some embodiments, “active” may also be used in reference to“low” periods, while inactive is used in reference to “high” periods.For example, in the case of a digital signal, “active” and “inactive”periods may simply be used to refer to the alternate states of thedigital signal. In some cases, “active” periods may reference intervalswhere a signal pulses in coordination with the speed control PWM signal114 (or would pulse in coordination with the speed control signal iflogically combined with the speed control signal, as described herein),as described herein, while “inactive” periods may reference intervalswhere a signal does not pulse in coordination with the speed control PWMsignal 114 (or would not pulse in coordination with the speed controlsignal if logically combined with the speed control signal, as describedherein).

As can be seen in FIG. 3A, in some embodiments, the φA and φB signalsare shifted in phase relative to one another by 90°, which correspondsto 30° of angular rotor rotation. In some embodiments, the Hall effectsensors output a “high,” or “active,” value in the presence of amagnetic north pole and a “low,” or “inactive,” value in the presence ofa magnetic south pole, though the converse can also be true. Otherconfigurations are also possible depending, for example, upon the typeof Hall effect sensors used. In addition, the high and low values can bereversed.

In FIG. 3A, a series of schematic representations 310, 312, 314, 316,and 318 of the rotor and stator of the BLM are shown below the signalwaveforms φA 302 and 9B 306. Each of these schematics represents thestate of the BLM during one of the delineated rotational phases. Forexample, schematic 310 represents the state of the BLM as the rotorrotates from 0°-30°. Each of the magnetic poles of the rotor isrepresented by a bold face “N” for a magnetic north pole or a bold face“S” for a magnetic south pole. The states of the electromagnets in thestator are represented in a similar manner (but are not in bold face),where φA1 and φA2 are the first and second electromagnets of the φAgrouping, and φB1 and φB2 are the first and second electromagnets of theφB grouping. Schematics 312, 314, 316, and 318 represent the state ofthe BLM during subsequent 30° angular phases of rotation.

As illustrated by schematics 310 and 312, magnetic pole φA1 of thestator is energized as a magnetic north pole during the rotation of therotor from 0°-60°. After 60° of rotation, the current through magneticpole φA1 is reversed so as to create a magnetic south pole. A similarpattern can be noted for each of the electromagnets in the statorwherein the polarity of each of the electromagnets is reversed every 60°of rotation. It can be seen from the schematics 310, 312, 314, 316, and318 that this pattern according to which the electromagnets in thestator are energized creates magnetic fields that interact with themagnets of the rotor to cause a rotational force. Again, the transitionsof the φA and φB coils are offset by 90°, which corresponds to 30° ofangular rotor rotation. The direction of this offset, whether forward orbackward in time, determines whether the rotor rotates in a clockwisefashion or a counterclockwise fashion.

The phase logic circuit 9 receives the φA and φB outputs from the Halleffect sensors as inputs. In general, the phase logic circuit 9 createsoutput signals, based on these inputs, which are used to properly phasethe timing and direction of energizing current through the statorelectromagnets (i.e., φA1, φA2, φB1, and φB2) so as to achieve rotorrotation. For example, for the BLM illustrated in FIG. 2A, the phaselogic circuit 9 energizes one of the φA electromagnets to serve as anorth magnetic pole while the other is energized as a south magneticpole (e.g., by oppositely wrapping the two φA electromagnets) for 60° ofangular rotation of the rotor. Similarly, the phase logic circuit 9energizes one of the φB electromagnets to serve as a north magnetic polewhile the other is energized as a south magnetic pole (e.g., byoppositely wrapping the two φB electromagnets) for a period of 60° ofangular rotation, but a 60° period of angular rotation that is 90° outof phase (which corresponds to 30° of angular rotation of the rotor)with the signals to the φA electromagnets. This can be seen by referenceto the schematics 310, 312, 314, 316, and 318 in FIG. 3A. After each 60°period of angular rotation, the magnetic polarity of the φAelectromagnets is switched, as is the magnetic polarity of the φBelectromagnets.

The phase logic circuit 9 also receives a PWM speed control input fromthe microprocessor 10. In some embodiments, The PWM input signal is usedto create a train of pulses that energize each of the electromagnets ofthe stator. The duty cycle of the pulses that energize theelectromagnets can be varied so as to change the average current througheach of electromagnets thereby varying the rotational force applied byeach electromagnet and, thus, the speed of rotation of the rotor. Asdescribed herein, the microprocessor 10 can control the duty cycle ofthe PWM signal 320 based on inputs related to, for example, the speed,the torque, or the temperature of the BLM.

FIG. 4A is a view of a phase logic control circuit 9 used in someembodiments. The illustrated phase logic control circuit can be used,for example, to control BLMs such as the 2+3 motor of FIG. 2A (a 2 phasearmature combined with a 3 phase rotor) and the 2 phase motor of FIG.2B. Referring to FIG. 4A, the phase logic control circuit 9 receivesinputs from two Hall effect sensors (H1, H2). These inputs from the Halleffect sensors are φA and φB, which are illustrated as waveforms 302 and306, respectively, in FIG. 3A. The φA and φB signals are each passedthrough an inverter, resulting in waveforms φA and φB, which are thelogical complements of φA and φB and are represented by waveforms 304and 308, respectively. In particular, φA is passed through inverter 118to create /φA, while the original φA signal is passed through the seriescombination of inverters 116 and 117 with no net change in the digitalφA signal. In a like manner, the φB signal is transformed to a φB signaland its complement, a /φB signal, via inverters 119, 120, and 121. Insome embodiments, inverters 116, 117, 119, and 120 may be dispensedwith. Moreover, in some embodiments the complements of the φA and φBsignals may be obtained in a different fashion, or may be senseddirectly from the BLM with one or more additional Hall effect sensorspositioned on the BLM.

In some embodiments, the φA, /φA, φB, and /φB signals are logicallycombined with the PWM speed control signal 114. For example, in someembodiments, a Boolean logical operation is performed to combine each ofthe φA, /φA, φB, and /φB signals, whether separately or collectively,with the PWM speed control signal 114. Such a Boolean logical operationcan be formed using, for example, logical AND, OR, NOR, NAND, and/or XORgates, or combinations thereof. In the embodiment illustrated in FIG.4A, the φA, /φA, φB, and /φB signals are inputted into first input portsof logical AND gates 124-127. The second input port of each of the ANDgates 124-127 receives the PWM speed control signal that is inputted tothe phase logic control circuit 9 at port 114 from the microprocessor10. The PWM signal is represented by waveform 320 in FIG. 3A. Themicroprocessor 10 can vary the duty cycle of the PWM signal in order tovary the rotational speed of the BLM in response to input signalsdescribed herein. In some embodiments, the frequency of the PWM signalis 20 kHz or greater. However, in other embodiments the frequency of thePWM signal may be less than 20 kHz. It should be understood that FIG. 3Ais not intended to specify any particular frequency of the PWM signal320 relative to the φA signal 302 and the φB signal 306 from the Halleffect sensors.

The outputs from the AND gates 124-127 are signals A, Ā, B, and B,respectively. Signal A is represented by waveform 322 in FIG. 3A. Asillustrated, signal A is “high” whenever both the φA and the PWM signalsare “high.” Signals Ā, B, and B are similarly represented by waveforms324, 326, and 328, respectively.

Each of the signals A, Ā, B, and B is inputted into a four-row logicswitch 128. The four-row logic switch 128 may be embodied by, e.g., the74HC241 IC available from Philips Semiconductors. The four-row logicswitch 128 has two states which are controlled by the F/R_CTRL signalfrom the microprocessor 10. As discussed herein, the F/R_CTRL signalcontrols whether the rotor of the BLM rotates in a clockwise or acounterclockwise fashion. The two states of the four-row logic switch128 are illustrated in FIG. 4B. FIG. 4B illustrates one half of thelogic switch 128 while in the first state and while in the second state.In the first state, the upper input of the top half of the logic switch(i.e., the input tied to the output of AND gate 124) is coupled to theupper output, while the lower input of the top half of the logic switch(i.e., the input tied to the output of AND gate 125) is coupled to thelower output. As described herein, the outputs of the logic switch areused to control gate drive circuitry 7 and power switches 4, which inturn drive the armature coils of the BLM stator.

When the F/R_CTRL signal is operated to place the logic switch 128 inthe second state, the upper input of the top half of the logic switch(i.e., the input tied to the output of AND gate 124) is coupled to thelower output, while the lower input of the top half of the logic switch(i.e., the input tied to the output of AND gate 125) is coupled to theupper output. This reversal causes the phase offset between the φA andthe φB windings of the armature to be reversed, resulting in thereversal of the direction of rotation of the rotor.

Signals A, Ā, B, and B are outputted from the phase logic controlcircuit 9. The complements of each of these signals are formed by asecond group of inverter gates 129-132 and are also outputted. Thus, theoutputs of the phase logic circuit 9 are A, Ā, B, and B, and theircomplements /A, /Ā, /B, and / B. These signals are then passed to gatedrive circuitry 7. Further, in some embodiments, the phase logic controlcircuit 9 has an output signal M_SENSE_A at port 93, and an outputsignal M_SENSE_B at port 94. The signals correspond to outputs from theHall effect sensors 3 and may be used by the microprocessor 10 to obtainthe rotational speed of the rotor of the BLM. In other embodiments,these signals are inputted to the microprocessor 10 directly from theHall effect sensors. Also, in some embodiments other means may be usedto obtain the rotational speed of the rotor of the BLM.

FIG. 4C illustrates a second embodiment of the phase logic controlcircuitry 9, which includes time delay logic. In FIG. 4C, as in FIG. 4A,the phase logic control circuit 9 receives inputs from first and secondHall effect sensors 3. The phase logic control circuit 9 also includesinverters 116-121, the PWM signal 114, logical AND Gates 124-127, andthe four-row logic switch 128. Each of these components has a functionin the phase logic control circuit 9 illustrated in FIG. 4C that issimilar to what is described herein with reference to FIG. 4A. Inaddition, the phase logic control circuit 9 of FIG. 4C includes alogical XOR gate 115, pulse generators 122, 123, and logical AND Gates151-154.

The logical XOR gate 115 receives the signals φA and φB from the Halleffect sensors as inputs. The output of the logical XOR gate 115 is tiedto inputs of pulse generators 122, 123. In some embodiments, the outputof the XOR gate 115 is a frequency-doubled, and possibly phase-shifted,version of the φA and φB rotor position signals. The pulse generators122, 123 can be embodied by the 74HC123 IC available from PhilipsSemiconductors. The output of the first pulse generator 122 is tied toan input of each of the logical AND gates 151, 152. Likewise, the outputof the second pulse generator 123 is tied to an input of each of thelogical AND gates 153, 154. The outputs of the logical AND gates 151-154are tied to the inputs of the four-row logic switch 128, whose outputsare each ANDed with the PWM signal 114 by the logical AND gates 124-127.

FIG. 3B illustrates a set of example waveforms from the phase logiccontrol circuitry 9 illustrated in FIG. 4C. Waveforms 91 and 92represent the Hall effect sensor signal inputs φA and φB, respectively.As described herein, in some embodiments the φA and φB signals are 90°(which corresponds to 30° of angular rotation of the rotor of the 2+3BLM of FIG. 2A) out of phase with one another. The EXOR signal 113 ishigh whenever either the φA or the φB is high but not both. The EXORsignal 113 is inputted to the pulse generators 122, 123, which haveoutputs Q1 133 and Q2 134, respectively. As illustrated in FIG. 3B, insome embodiments, the pulse generators 122, 123 generate either a highor low pulse in response to the transition edges of the EXOR signal 113.For example, the first pulse generator 122 generates low pulses inresponse to the positive transitions, or rising edges, of the EXORsignal 113, and the second pulse generator 123 generates low pulses inresponse to the negative transitions, or falling edges, of the EXORsignal 113. In some embodiments, the time duration of the low pulsesgenerated by the first and second pulse generators 122, 123 is in therange from approximately 200 us to approximately 600 us, though otherdurations are also possible and may be advantageous in some embodiments.In some embodiments, the parameters of the pulse generators 122, 123 canbe varied so as to control the width of the transition period. Onepurpose of the pulses generated by the pulse generators 122, 123 is tocreate a transition period between the signals that control the firstand second full bridge configurations of switches so as to reduce backEMF and back torque caused by the prior rise-up and prior fall-down ofthe motors rotating magnetic field. In addition, the transition periodhelps to avoid a short circuit fault condition in the full bridges, asdescribed herein. The transition period may also improve forward EMFand/or avoid a magnetic deep loss point. While FIG. 4C illustrates oneembodiment of circuitry for performing these functions, they can also beperformed by different circuitry, at a different location in the signalflow of the circuit, or both. In some embodiments, the length of thepulses generated by the first and second pulse generators 122, 123 isless than about ¼ of a period of the EXOR signal 113, or less than about⅛, or less than about 1/16 of a period of the EXOR signal 113. In someembodiments, the transition period is appreciably longer than settlingtimes of power switches that are used to drive the electromagnets of theBLM.

The outputs of the first and second pulse generators 122, 123 are ANDedtogether with the φA, /φA, φB, and /φB signals using the logical ANDgates 151-154, as illustrated in FIG. 4C. the outputs of the logical ANDgates 151-154 are the A′ signal 99, the A′ signal 100, the B′ signal101, and the B′ signal 102. The A′ signal 99 corresponds generally tothe φA signal 91 but with active periods that have been shortened by thewidth of the pulse generated by pulse generator 122. The A′ signal 100corresponds generally to the /φA signal 96 but, again, with activeperiods that have been shortened by the width of the pulse generated bythe pulse generator 122. The same is true regarding the B′ signal 101,and the B′ signal 102 with respect to the φB signal 92 and in the /φBsignal 98. As illustrated in FIG. 3B, the XOR gate 115, the pulsegenerators 122, 123, and the AND gates 151-154 temporally space activeperiods of, for example, the rotor position signal φA and its logicalcomplement. The same is true with regard to temporally spacing activeperiods of the rotor position signal φB and its logical complement. Thisresults in temporal spacing of forward polarity and reverse polaritydrive pulses in the signals of FIG. 3B labeled 41-42(PWM) and43-44(PWM), as described herein.

The A′ signal 99, the A′ signal 100, the B′ signal 101, and the B′signal 102 are transmitted to the logical AND gates 124-127 by way ofthe four-row logic switch 128. The PWM signal 114 is then ANDed witheach of these signals by the logical AND gates 124-127 in order tocreate pulse trains, as described herein. Ultimately, these signalscontrol the first and second configurations of full bridge switches(i.e., F1-F8), which drive the electromagnets of the BLM, as describedherein.

While FIGS. 4A and 4C each show that the speed control PWM signal 114 islogically combined with the BLM rotor position signals φA and φB withlogical AND gates (e.g., 124-127), other types of logic gates can alsobe used. For example, in some embodiments, the logical AND gates 124-127of FIGS. 4A and 4C can be replaced with logical NOR gates. In theseembodiments, for example, signals A and B consist of positive pulsesthat correspond to the PWM signal 114 whenever signals φA and φB arerespectively low, and signals A and B are low whenever signals φA and φBare respectively high. In addition, in some embodiments, the logical ANDgates 124-127 can be replaced with logical OR gates or with logical NANDgates. In these embodiments, for example, signals A and B consist ofintervals of negative pulses that correspond to the PWM signal 114.These intervals of pulses are separated by high signal intervals insteadof low signal intervals, as in the case where AND gates or NOR gates areused. Other types and/or combinations of logic gates can be used tocombine the rotor position signals φA and φB with the speed control PWMsignal 114.

Depending upon the particular logic gates used in a given embodiment,the gate drive circuitry (e.g., gate-dedicated ICs 71-74) may requiremodification (e.g., to compensate for intervals of pulses separated byhigh intervals instead of low intervals, as in the illustratedembodiments of FIGS. 4A and 4C) to appropriately control the powerswitches using the drive signals that result from the logicalcombination of the rotor position signals and the speed control PWMsignal. However, these modifications can be performed by a person havingordinary skill in the art based on the disclosure provided herein.

In some embodiments, the phase logic control circuitry 9 is implementedas a single integrated circuit, or chip, such as an Application SpecificIntegrated Circuit (ASIC). For example, all of the circuitry illustratedin FIG. 4C may be embodied in a single integrated circuit. In someembodiments, the phase logic control circuitry 9, excluding the four-rowlogic switch 128 and/or the pulse generators 122, 123 is implemented asa single integrated circuit, or chip, such as an Application SpecificIntegrated Circuit (ASIC). In some embodiments of the BLM circuitry, thephase logic control circuitry and the gate drive circuitry areimplemented as a single integrated circuit, or chip, such as anApplication Specific Integrated Circuit (ASIC).

Gate Drive Circuitry

The outputs A, Ā, B, and B, and their complements /A, /Ā, /B, and / B,from the phase logic circuit 9 are passed to gate drive circuitry 7,which interfaces between the phase logic circuit 9 and two separate fullbridge configurations of power switches 4 that drive the φA and φBelectromagnets of the BLM. Although the signals A, Ā, B, and B, andtheir complements /A, /Ā, /B, and / B, are those that are physicallypassed to the gate drive circuitry 7 and can be considered drivesignals, the signals at various different points in FIGS. 4A and 4C canlikewise be considered as drive signals. The gate drive circuitry 7 andthe power switches 4 are illustrated in FIG. 5A. Referring to FIGS. 4Aand 5A, the outputs 105, 106, 107, and 108 of the 2 phase logic controlcircuit 9 are respectively connected to first gate-dedicated ICs 71, 73for driving full bridge switches F1, F2, F3, and F4 which power the φAelectromagnets (e.g., those illustrated in FIG. 2A), while the outputs109, 110, 111, and 112 are connected to second gate-dedicated ICs 72, 74for driving full bridge circuits F5, F6, F7, and F8 of the φBelectromagnets (e.g., those illustrated in FIG. 2A). The gate-dedicatedICs may be embodied by, e.g., the IRS2106 IC available fromInternational Rectifier.

In some embodiments, each of F1-F8 is a field effect transistor (FET).However, other types of switching devices, such as insulated-gatebipolar transistors, for example, may also be used. Switches F1-F4 arearranged in a first full bridge configuration that drives the φAelectromagnets, while switch is F5-F8 are arranged in a second fullbridge configuration that drives the φB electromagnets. In otherembodiments, half bridge configurations of switches may be used. Theoutputs 105, 106, 107, and 108 of the phase logic control circuit 9switch the first full bridge (F1-F4) and the outputs 109, 110, 111, and112 of the phase logic control circuit 9 switch the second full bridge(F5-F8). The outputs 41, 42 are fed to the φA armature windings, whilethe outputs 43, 44 are fed to the φB armature windings. These outputsdrive the BLM in the manner described herein. The BLM may be embodied bya 2 phase and 3 phase combined type brushless BLM (FIG. 2A) or aconventional 2 phase brushless BLM (FIG. 2B).

FIG. 5B illustrates two states of one of the full bridge circuits usedto supply power to the armature windings of a BLM. For example, asillustrated in FIG. 5B, the signals A, Ā, /A, and /Ā control the fullbridge arrangement of switches that includes F1-F4 (by way of gate drivecircuitry 7). Signals A and Ā are illustrated in FIG. 3 as waveforms 322and 324. While signals /A and /Ā are not explicitly illustrated in FIG.3, they are the complements of signals A and Ā and can be easily derivedfrom waveforms 322 and 324. Signals A, Ā, /A, and /Ā are coupled to thegate drive circuitry 7 and the power switches 4 in such a manner as toalternate the first full bridge of switches F1-F4 between the two statesillustrated in FIG. 5B. For example, while in the first state, the fullbridge allows current to flow from a power source through the φAelectromagnets in a first direction. Conversely, current is permitted toflow from a power source to the φA electromagnets in a second directionwhen the full bridge F1-F4 is in the second state. This reversal of thedirection of current reverses the magnetic polarity of the φAelectromagnets in the stator. Signals B, B, /B, and /B control thesecond full bridge of switches F5-F8 in a similar manner.

As described herein, in some embodiments of the BLM illustrated in FIG.2A, the magnetic polarity of the φA electromagnets is switched every 60°of angular rotation of the rotor. The same is true of the φBelectromagnets but at a timing 90° out of phase with the φAelectromagnets (which corresponds to 30° of angular rotation of therotor). It should be understood, however, that the phase control logic9, the gate drive circuitry 7, and the power switches 4 illustrated inFIGS. 4A, 4C, 5A, and 5C can also be used with different BLMs, such as,for example, the two phase motor illustrated in FIG. 2B. When used withthe two phase motor illustrated in FIG. 2B, the input signals from theHall effect sensors would be somewhat altered (e.g., their frequencies,phase relationships, etc.) owing to the different angular relationshipsbetween the magnetic poles of the rotor, which would affect theexcitation of the φA and the φB electromagnets. However, the circuitryitself for controlling the BLM of FIG. 2B can be substantially the sameas the circuitry that has been described for controlling the BLM of FIG.2A.

In some embodiments, each of signals A, A, /A, /Ā, B, B, /B, and / Bconsists of a train of pulses. The duty cycles of these pulses variesaccording to the duty cycle of the PWM signal 320. As described herein,the duty cycles of these pulses can be varied to change the averagecurrent through the armature windings of the BLM as a means to controlthe rotational speed of the rotor.

FIG. 5C illustrates the gate drive circuitry 7 and the power switches 4that are controlled by the phase logic control circuit 9 of FIG. 4C. Thegate-dedicated ICs 71-74 and the power switches F1-F8 operates similarlyto what is described herein with respect to FIG. 5A. FIG. 3B illustratesthe output of the first full bridge configuration of switches, which iswaveform 41-42(PWM). The signal is made up of a train of positivevoltage pulses which energize the electromagnets of the BLM with currentin a first direction. The positive pulses are followed by a low voltage(e.g., zero voltage) transition period, which is created using the pulsegenerator 122. In some embodiments, the transition period is appreciablylonger than the settling times of the power switches so as to provide asufficient safety margin between the switching off of one pair ofswitches in the full bridge and the switching on of the other pair ofswitches. The safety margin avoids a fault condition where a direct pathfrom the positive voltage power supply to the negative voltage powersupply could exist. The transition period is then followed by a train ofnegative voltage pulses which energize the electromagnets of the BLMwith a current in a second direction, opposite from the first. Thesenegative pulses are followed by another transition period and anothertrain of positive pulses, etc. The output of the second full bridgeconfiguration of switches (F5-F8) is similarly illustrated in FIG. 3B aswaveform 43-44(PWM). As described herein, in some embodiments, theoutput of the second full bridge configuration of switches is 90° out ofphase with the output of the first full bridge configuration of switches(which corresponds to 30° of angular rotation of the rotor of the BLM).

FIG. 6 is a detailed circuit view of a control system being used in someembodiments.

Referring to FIGS. 1 and 6, pre-determined data of a plurality ofoperation control commands from the factory program device 12, where thepre-determined data are stored, are inputted into RS485 13 of someembodiments. RS485 13 includes RS485 communication IC chip 131 having atransmitting line 12T and a receiving line 12R capable of communicatingwith the factory program device 12. The transmitting and receivingoutputs of RS485 13 and the signal control (CTR) outputs arerespectively inputted into the microprocessor 10 through opto-isolationcouplers 13T, 13R, and 13CTR. A switch 103S is a means for changing arotational direction of the motor 2 by simple on-off operation and isconnected to ground. A High (H) or Low (L) signal 103I by this switch103S is inputted into the microprocessor 10 through an opto-isolationcoupler 11 b. The H or L signal 103I is inputted during an operation,the microprocessor 10 waits for a certain period of time until itidentifies that the rotation of the motor 2 almost stops. Thereafter,the microprocessor 10 transmits a control signal for switching arotational direction, as a switching input 103, to the 2 phase logiccontrol circuit 9.

In the meantime, a DC voltage +Vm applied to the motor 2 is divided byresistance 171 and resistance 172 in the voltage detection circuit 17. Adivided voltage is again smoothened by a condenser 173 and thesmoothened voltage is inputted into the microprocessor 10. Resistance 83is 24 connected to between the power switch circuit 4 and ground voltage−Vm. A voltage across both ends of the resistance 83, which isproportional to a current value flowed in the power switch 4, passesthrough a integral filter circuits 84, 85, and 86 and is inputted into avoltage comparison amplifier 81. The output of the voltage comparisonamplifier 81 is inputted into the microprocessor 10 and then themicroprocessor 10 calculates a load current value of the motor 2.

The temperature detection sensor 16, which may be embodied by atransistor or a thermistor for outputting a voltage signal proportionalto a temperature, may be mounted on a case or an armature of the motor2. The output signal of the temperature detection sensor 16 is inputtedinto the microprocessor 10, and the microprocessor 10 may transmit asignal for indicating an abnormal condition of the motor 2 to the relayswitch 18. The relay switch 18 may be embodied by a switch where acontact point of a circuit is switched in an on-off manner. Themicroprocessor 10 also transmits a rotation speed data signal 11 c ofthe motor 2 to a connection port 152 of the central control system 15through the opto-isolation coupler 11 a.

In some embodiments, anyone of the DC voltage signal (0-10 Vdc) 151 orthe PWM signal 151 for controlling the speed of the motor 2 from thecentral control system 15 is inputted into the opto-isolated speedcommand signal processing interface 14 through one port. In case thatthe DC voltage signal (0-10 Vdc) 151 for controlling the speed of themotor 2 is inputted, the DC voltage signal (0-10 Vdc) 151 forcontrolling the speed of the motor 2 is transmitted to an input PB2 ofthe microprocessor 10 through a linear amplifier 141. In case that thePWM signal 151 for controlling the speed 25 of the motor 2 is inputted,the PWM signal 151 for controlling the speed of the motor 2 is outputtedthrough a transistor 142 and then passes through a differential circuits142,143, and 144, each of which is comprised of a condenser 143 andresistance 144, and then is transmitted to an input PB1 of a secondmicroprocessor 146. Therefore, the opto-isolated speed command signalprocessing interface 14 of some embodiments may process the DC voltagesignal (0-10 Vdc) 151 and the PWM signal 151 for controlling the speedof the motor 2, respectively. For this purpose, the secondmicroprocessor 146 includes a program having algorithms, which outputs aPWM output signal where a width of the PWM output signal with a specificfrequency (e.g., 80 Hz) is exactly modulated in proportion to a rate(0-100%) of voltage with a range of 0 to 10 Vdc in case of the DCvoltage signal (0-10 Vdc) 151 for controlling the speed of the motor 2,while outputs a PWM output signal where a width of the PWM output signalwith a specific frequency (e.g., 80 Hz) is exactly modulated inproportion to a pulse width modulation rate (0-100%) in case of the PWMsignal 151 for controlling the speed of the motor 2. The output of thesecond microprocessor 146 is connected to the input 80 Hz_PWM_IN of themicroprocessor 10 through the opto-isolation coupler 145.

In the microprocessor 10 and the logic control circuit 9 being used in acontrol system of a motor for the pump 2 according to some embodiments,not only various operations, which are required when controlling themotor 2, may be selected as described in detail above, but also datainformation relating to operation current, voltage, speed, andtemperature which are processed by the microprocessor 10 is possible tobe transmitted to 26 an external system (e.g., a monitor, a personalcomputer, or a data recording device, etc.) through either RS485 13connected to the microprocessor 10 or a separate communication device.As a result, logging the operation-related data information describedabove is available so that it is possible to monitor any troubles,operation efficiency, and a condition on a stable operation of an HVACor a pump in real time by analyzing the operation conditions through 24hours.

As various modifications could be made in the constructions and methodherein described and illustrated without departing from the scope of theinvention, it is intended that all matter contained in the foregoingdescription or shown in the accompanying drawings shall be interpretedas illustrative rather than limiting. Thus, the breadth and scope of theinvention should not be limited by any of the above-described exemplaryembodiments, but should be defined only in accordance with the followingclaims appended hereto and their equivalents.

1. An electric motor comprising: windings; a power supply circuit configured to convert an electric power input to a first electric power, a second electric power and a third electric power; a logic circuit powered with the first electric power and configured to provide logic signals; a power switching circuit configured to supply the second electric power to the windings based on the logic signals; an interface circuit powered with the third electric power and configured to interface between internal circuits of the electric motor and one or more devices external to the electric motor; and wherein the third electric power is electrically isolated from the first and second electric powers, wherein the interface circuit is electrically isolated from the internal circuits and optically connected to the internal circuits so as to provide data communication between the internal circuits and the one or more external devices via optical connection to the internal circuits.
 2. The motor of claim 1, wherein the interface circuit is configured not to receive an electric power other than the third electric power.
 3. The motor of claim 1, wherein the electric power input is an AC power input.
 4. The motor of claim 1, wherein the power supply circuit comprises a DC/DC converter configured to supply the third electric power to the interface circuit.
 5. The motor of claim 1, wherein the third electric power has voltage of about 12 volts.
 6. The motor of claim 1, wherein the first electric power has voltage of 12-15 volts.
 7. The motor of claim 1, further comprising an opto-isolator configured to optically connect the interface circuit and the internal circuits of the electric motor.
 8. The motor of claim 1, further comprises a microprocessor which is optically connected to the interface circuit and configured to receive data via the interface circuit from one of the one or more devices external to the electric motor.
 9. The motor of claim 8, wherein the microprocessor is configured to receive at least one operation control command selected from the group consisting of a non-regulated speed control (NRS) command, a regulated speed control (RS) command, a constant torque control command, a constant air flow control command, a clockwise rotation command and a counter-clockwise (CCW) rotation control command. 